Cytotoxic therapy for breast cancer

The purpose of cytotoxic therapy is to destroy cancer cells or at least disrupt their growth.

Cytotoxic drugs are usually administered intravenously as injections into a vein or as a drip (infusion) at the hospital’s chemotherapy outpatient clinic. Some cytotoxic drugs are given as tablets or capsules,which can be taken at home.

A course of chemotherapy comprises a combination of various cytotoxic drugs. The treatment is given in a number of cycles because not all cancer cells are destroyed simultaneously; each cycle destroys only a certain proportion of the cancer cells. In between the cycles, the normal, healthy cells recover faster than the remaining cancer cells.

The oncologist plans the cytotoxic therapy individually for each patient, depending on the type, size, stage and grade of the breast cancer at the time of diagnosis.

The most common form of breast cancer is treated with the CEF combination (C = cyclophosphamide, E = epirubicin, F= fluorouracil). It is administered intravenously. The treatment is begun one month after the surgery. The dosage is calculated according to the area of the patient’s skin. The treatment is repeated at three-week intervals, provided that the normal blood cells recover enough in between. Usually the treatment is repeated a total of six times.

If the breast tumour has grown relatively big and the cell morphology indicates that it is more aggressive, a cytotoxic drug called Taxotere is used. It is administered intravenously. The treatment is begun one month after the surgery and is repeated three times at three-week intervals. After three cycles, the treatment is continued with the CEF combination, administered three times at three-week intervals.

Taxotere treatment is combined with Herceptin treatment if there are HER2 receptors in the breast cancer cells. Herceptin is given together with Taxotere nine times at one-week intervals. Herceptin is not a cytotoxic drug but a targeted drug that blocks receptors.

When treating inflammatory breast cancer (the breast is red and swollen), three cycles of chemotherapy at three-week intervals are given already before the surgery. The surgery is performed between cycles, and another 3-6 cycles of chemotherapy are given after the surgery according to the oncologist’s instructions.

If the white blood cell count is too low after chemotherapy, the growth of white cells is stimulated by G-CSF treatment (e.g. a drug called Neupogen). This medication is usually given orally as tablets.

Side effects of chemotherapy

Most of the symptoms relating to the side effects of chemotherapy can be prevented or alleviated.

Many normal, fast-regenerating healthy cells of the body are sensitive to cytotoxic drugs. Millions of new cells are produced every day in, for example, the bone marrow, as well as in the scalp and in the mucous membranes of the mouth and the intestines.

Chemotherapy also destroys some of the healthy cells in the bone marrow, scalp and mucous membranes. Side effects related to this include low blood counts, hair loss, and digestive and intestinal problems.

Hair and chemotherapy

The regeneration of cells in the scalp can be disrupted by chemotherapy, causing hair loss in some patients. Sometimes hair comes off in large clumps. Hair loss can also occur on other parts of the body, including the eyebrows, beard and pubic hair.

The nails are part of the skin and can also fall out. All patients receiving chemotherapy can be provided with a wig. When chemotherapy is over, hair and body hair will grow back.

Nausea caused by chemotherapy

Anti-nausea medication is given well before the beginning of chemotherapy.

It will be continued as long as there are symptoms.

Appetite during treatments

In addition to chemotherapy, the cancer itself can cause loss of appetite and weight.

It is advisable to eat small portions at frequent intervals.

Cold food causes less nausea than hot food and might be easier to eat if mucous membranes in the mouth have been damaged.

Nutritional drinks are recommended if eating is difficult.

Mucous membranes

The body’s mucous membranes are not always regenerated fast enough during cancer treatment.

This can cause mouth ulcers, a dry mouth, nausea, diarrhoea and intestinal problems.

The symptoms will disappear after a while once chemotherapy ends.

Blood

The red blood cells transport oxygen to all organs and tissues of the body. Chemotherapy decreases the number of red blood cells in the body. This can result in a lower level of haemoglobin, which can cause tiredness and paleness.

The white blood cells protect the body against bacteria and viruses. When the body’s white blood cell count drops, susceptibility to infection increases. The risk of infection is usually the highest 7-14 days after chemotherapy. It is advisable to avoid contact with people with a cold during that time. If a patient develops a high temperature at home, she should contact the clinic.

Blood platelets (thrombocytes) help the blood to coagulate and wounds to heal.

Usually the bone marrow manages to recover and the blood counts return to normal between cycles of chemotherapy. This will be monitored by blood tests.

Chemotherapy may be followed by hormone therapy, i.e. anti-oestrogen therapy, in order to reduce the oestrogen level as far as possible. This therapy is used if oestrogen and progesterone receptors are found in the tumour.